Prevalence of blaZ Gene and Performance of Phenotypic Tests to Detect Penicillinase in Staphylococcus aureus Isolates from Japan

Guidelines recommend that clinical laboratories perform phenotypic tests (nitrocefin-based test and penicillin 10-U [P10] or 1-U [P1] zone edge tests) to detect penicillinase in Staphylococcus aureus isolates. This study aimed to assess the prevalence of blaZ encoding penicillinase and perform various phenotypic tests in S. aureus isolates from Japan. We prospectively collected 200 methicillin-susceptible S. aureus isolates from June 2015 to January 2016 and performed six phenotypic tests (nitrocefin-based test, P10 zone edge test/P10 diffusion test, penicillin 2-U [P2] zone edge test/P2 diffusion test, and cloverleaf test) on each sample. We confirmed the presence of blaZ (two blaZ-positive isolates) using PCR. Using blaZ PCR as a standard, we observed a low sensitivity (50%) and positive predictive value (PPV, 50%) of the nitrocefin-based test, low PPV (18.2%) of the P10 zone edge test, low sensitivity (50%) of the P10 diffusion test, low PPV (50% and 22.2%) of the P2 zone edge test and P2 diffusion test, respectively, and low sensitivity (50%) of the cloverleaf test. These data suggest a low performance (sensitivity and PPV) of these six phenotypic tests because of the low prevalence (1%) of blaZ in S. aureus isolates from Japan.

Escherichia Coli productora de Nueva Delhi metalo-ß-lactamasa en Colombia: reporte de caso / Escherichia Coli producing New Delhi metallo-ß-lactamase in Colombia: A case report

Notificamos un caso de infección por Escherichia coli productora de Nueva Delhi metalo-b-lactamasa (NDM) en un paciente que desarrolló un absceso subcapsular hepático como complicación de una colecistectomía laparoscópica. La NDM es una carbapenemasa adquirida tipo Ambler B, que confiere resistencia a todos los b-lactámicos, excepto al aztreonam, aunque existen reportes de resistencia a este último. En Colombia, la primera descripción de cepas productoras de NDM se realizó en aislamientos de Klebsiella pneumoniae en una unidad de cuidados intensivos neonatales en Bogotá. Desde entonces se han realizado reportes de distintas cepas, siendo esta la primera reportada en el país relacionada con Escherichia coli productora de NDM.

We report a case of infection by New Delhi metallo-β-lactamase (NDM)-producing Escherichia coli in a patient who developed a subcapsular hepatic abscess as a complication of laparoscopic cholecystectomy. NDM is an acquired carbapenemase Ambler class B, which confers resistance to all b-lactams except aztreonam, although there are reports of resistance to the latter. In Colombia, the first report of NDM-producing strains was made on isolates of Klebsiella pneumoniae in a neonatal intensive care unit in Bogota. There have since been reports of different strains, marking the first reported in the country of NDM-producing Escherichia coli.

Enterobacterias productoras de betalactamasas de espectro extendido en muestras fecales en el Instituto Nacional de Salud del Niño, Perú / Extended-spectrum beta-lactamase (ESBL)-producing enterobacteriaceae in fecal samples at the National Institute of Child Health, Peru

Objetivos. Describir la frecuencia de enterobacterias productoras de betalactamasas de espectro extendido (BLEE) en muestras fecales en el Instituto Nacional de Salud del Niño, Lima, Perú. Materiales y métodos. Se analizaron muestras de heces recibidas entre julio de 2012 y marzo de 2013, se trabajó con colonias sospechosas de ser enterobacterias productoras de BLEE que se desarrollaron en el agar Karmali; se realizó la identificación bioquímica por métodos convencionales y la confirmación del fenotipo BLEE. El análisis genotípico para detectar el gen de betalactamasa de la familia CTX-M se realizó por PCR. Resultados. De 235 muestras fecales se aisló un 64,2% de enterobacterias productoras de BLEE siendo Escherichia coli 86,1%, Klebsiella pneumoniae 7,9%, Salmonella sp. 2,6%, Enterobacter cloacae 2,0% y Proteus mirabilis 1,3%. El 89,1% de las enterobacterias productoras de BLEE presentaron el gen blaCTX-M. Se encontró una alta resistencia al ácido nalidíxico 84,8%, ciprofloxacina 74,2% y trimetoprimsulfametoxazol 81,5%. La resistencia a la amikacina fue de 1,3% y todos los aislados fueron sensibles al imipenem y meropenem. Conclusiones. Se encontró una alta frecuencia de enterobacterias productoras de BLEE en muestras fecales de pacientes ambulatorios atendidos en los consultorios externos y emergencia del Instituto Nacional de Salud del Niño en Perú.

Objectives. To describe the frequency of extended-spectrum beta-lactamase (ESBL)-producing enterobacteriaceae in fecal samples at the National Institute of Child Health, Lima, Peru. Materials and methods. Stool samples received between July 2012 and March 2013 with colonies suspected to be ESBL-producing enterobacteriaceae that developed in Karmali agar were analyzed. Conventional methods were performed for biochemical identification and the confirmation of the ESBL phenotype. Genotypic analysis to detect the beta-lactamase gene CTX-M family was performed by PCR. Results. Of the 235 fecal samples analyzed, 64.2% of ESBL-producing enterobacteria was isolated being 86.1% Escherichia coli, 7.9% Klebsiella pneumoniae, 2.6% Salmonella sp, 2.0% Enterobacter cloacae, and 1.3% Proteus mirabilis. 89.1% of the ESBL-producing enterobacteria presented the CTX-M gene. We found high resistance to nalidixic acid 84.8%, 74.2% ciprofloxacin and trimethoprim-sulfamethoxazole 81.5%.The resistance to amikacin was 1.3% and all isolates were susceptible to imipenem and meropenem. Conclusions. A high frequency of ESBL-producing enterobacteria was found in fecal samples of outpatients seen in the outpatient and emergency departments of the National Institute of Child Health of Peru.

Actividad inhibitoria de dihidroxifenil propenona sobre betalactamasas de Enterobacter cloacae: estudio preliminar en el desarrollo de fármacos para enfrentar la resistencia bacteriana / Inhibitory activity of dihydroxy-phenyl-propenone on betalactamase of Enterobacter cloacae : Preliminary study for drug development to overcome bacterial resistance

Introducción . Los microorganismos patógenos como Enterobacter cloacae producen betalactamasas que les confieren resistencia frente a los antibióticos betalactámicos; se ha identificado, además, la actividad limitada de los inhibidores enzimáticos, de modo que la única posibilidad de enfrentar la resistencia es el diseño de nuevos fármacos y su uso racional. Objetivo. Evaluar el efecto de la chalcona dihidroxifenil propenona sobre un aislamiento clínico de E. cloacae y sobre la betalactamasa aislada a partir de este microorganismo resistente como un aporte en la búsqueda de compuestos inhibidores de las betalactamasas. Materiales y métodos. Se sintetizó la chalcona dihidroxifenil propenona y se evaluó su efecto sobre el aislamiento clínico de E. cloacae para determinar la concentración inhibitoria mínima mediante el método de microdilución en caldo y con la betalactamasa purificada mediante cromatografía de afinidad se realizaron estudios espectrofotométricos de cinética enzimática. Resultados. La concentración inhibitoria mínima de la dihidroxifenil propenona sobre E. cloacae fue de 35 µg/ml; el porcentaje de recuperación de la betalactamasa a partir del microorganismo fue de 31,75 %; en el estudio cinético se evidenció actividad inhibitoria de acuerdo con los parámetros cinéticos de V max =1,7 x 10 -3 µM/minuto y K M´ =2330 µM. Conclusión. La chalcona dihidroxifenil propenona ejerce su actividad inhibitoria por medio de la interacción con la betalactamasa y, de esta manera, protege la integridad estructural de los antibióticos betalactámicos; dicho efecto sinérgico la convierte en un compuesto promisorio en la búsqueda de alternativas para enfrentar la resistencia bacteriana.

Introduction: Enterobacter cloacae is a pathogenic microorganism with the ability to produce betalactamase enzymes, which makes them resistant to betalactamic antibiotics. Additionally, the limited activity of enzymatic inhibitors has been identified, and, therefore, the design of new drugs and the promotion of their rational use are the only possibilities to overcome this problem. Objective: The aim of this research was to evaluate the effect of dihydroxy-phenyl-propenone on a clinical isolate of E. cloacae , as well as its activity on a betalactamase isolated from this resistant microorganism in order to contribute to the search for new betalactamase inhibitors. Materials and methods: Dihydroxy-phenyl-propenone chalcone was synthesized and evaluated on a clinical isolate of E. cloacae to determine the minimum inhibitory concentration by broth microdilution; once the betalactamase enzyme was purified by affinity chromatography, a spectrophotometric analysis was done to evaluate its kinetic activity. Results: The minimum inhibitory concentration value of dihydroxy-phenyl-propenone on E. cloacae was 35 µg/ml; the recovery percentage of the betalactamase from the microorganism was 31.75% and the kinetic parameters were V max =1.7 x 10 -3 µM/min and K M = 2330 µM, which show an important inhibitory activity. Conclusion: Dihydroxy-phenyl-propenone has shown inhibitory activity on betalactamase enzymes and the ability to protect the chemical integrity of betalactamic antibiotics; this synergistic effect turns it into a promising compound in the search for new alternatives to overcome bacterial resistance.

Factores de riesgo en infección y colonización por escherichia coli y klebsiella pneumoniae productoras de betalactamasas de espectro extendido / Risk factors in extended-spectrum betalactamase producing escherichia coli and klebsiella pneumoniae infection and colonizatión

Las betalactamasas de espectro extendido (BLEE) son enzimas producidas por bacterias Gram negativas, que tienen la capacidad de destruir el anillo betalactámico de las cefalosporinas de tercera generación, permitiendo a la bacteria continuar con el entrecruzamiento del peptidoglicano y con la formación de pared celular sin alteraciones. Descritas en los años ochenta su diseminación y aumento en la incidencia en todos los continentes ha llevado al incremento de la morbilidad y mortalidad de los pacientes, prolongación de los días de estancia hospitalaria, mayor demanda de uso de carbapenémicos e incremento de los costos de la atención en salud. Predecir el patrón de resistencia del microorganismo que infecta a un paciente con base en el análisis de los factores de riesgo asociados permite la óptima elección de la antibioticoterapia empírica, racionalizando el uso de los antibióticos de amplio espectro disponibles y mejorando la sobrevida de los pacientes. Para esta revisión se realizó una búsqueda de los estudios de casos y controles en los cuales se investigaron los factores de riesgo asociados con infección o colonización por bacterias productoras de BLEE a saber: exposición previa a antibióticos, estancia en UCI, uso de catéter vesical, catéter central o ventilación mecánica...

Extended-spectrum betalactamases (ESBLs) are enzymes produced by gram- negative bacteria which are capable of destroying the betalactamic ring of third-generation cephalosporins enabling the bacteria to continue the peptidoglican crosslinking process resulting in unaltered integrity of the bacterial cell wall. ESBLs were first detected in the 1980s. Its incidence increased and dissemination in all continents has lead to greater morbidity and mortality rates, prolonged hospitalization, greater usage of carbapenems and rising health care costs. Prediction of resistance patterns of infecting microorganisms based on the analysis of the risk factors associated facilitate optimal selection of empirical antibiotic treatment, rationalized use of available broad spectrum antibiotics and improvement of patient survival. This review searched for case studies and follow up trials which investigated the risk factors associated with ESBL producing bacterial infection or colonization, that is, previous exposure to antibiotics, hospitalization at the ICU, urinary catheterization, central venous catheterization and mechanical ventilation...

Antimicrobial resistance of Staphylococcus spp. from small ruminant mastitis in Brazil / Resistência antimicrobiana de Staphylococcus spp. de mastite de pequenos ruminantes no Brasil

The study aimed to determine the antimicrobial resistance patterns and to identify molecular resistance markers in Staphylococcus spp. (n=210) isolated from small ruminant mastitis in Brazil. The antimicrobial resistance patterns were evaluated by the disk diffusion test and by detection of the presence of mecA, blaZ, ermA, ermB, ermC and msrA genes by PCR. The efflux pump test was performed using ethidium bromide and biofilm production was determined by Congo red agar test along with PCR for detection of the icaD gene. The isolates were most resistant to amoxicillin (50.0%), streptomycin (42.8%), tetracycline (40.4%), lincomycin (39.0%) and erythromycin (33.8%). Pan-susceptibility to all tested drugs was observed in 71 (33.8%) isolates and 41 Staphylococcus isolates were positive for the efflux pump. Although phenotypic resistance to oxacillin was observed in 12.8% of the isolates, none harbored the mecA gene. However, 45.7% of the isolates harbored blaZ indicating that beta-lactamase production was the main mechanism associated with staphylococci resistance to beta-lactams in the present study. The other determinants of resistance to antimicrobial agents ermA, ermB, ermC, and msrA were observed in 1.4%, 10.4%, 16.2%, and 0.9% of the isolates, respectively. In addition, the icaD gen was detected in 32.9% of the isolates. Seventy three isolates (54 from goats and 19 from sheep) were negative for all resistance genes tested and 69 isolates presented two or more resistance genes. Association among blaZ, ermA, ermB, ermC and efflux pump were observed in 17 isolates, 14 of which originated from goats and three from sheep. The data obtained in this study show the resistance of the isolates to beta-lactamics, which may be associated with the use of antimicrobial drugs without veterinary control.

O presente trabalho teve como objetivo determinar os padrões de resistência a agentes antimicrobianos e identificar marcadores moleculares de resistência em Staphylococcus spp. (n=210) isolados de mastite de pequenos ruminantes no Brasil. Os padrões de resistência a agentes antimicrobianos foram avaliados pelo teste de difusão em disco e pela detecção da presença dos genes mecA, blaZ, ermA, ermB, ermC e msrA via PCR. O teste da bomba de efluxo foi realizado utilizando brometo de etídio e a produção de biofime foi determinada pelo teste do vermelho congo em paralelo com o PCR para detecção do gene icaD. Os isolados foram mais resistentes a amoxicilina (50,0%), estreptomicina (42,8%), tetraciclina (40,4%), lincomicina (39,0%) e eritromicina (33,8%). Setenta e um (33,8%) isolados foram sensíveis a todas as drogas testadas e 41 foram positivos para a bomba de efluxo. Embora a resistência fenotípica a oxacilina tenha sido observada observada em 12,8% dos isolados, nenhum possuiu o gene mecA. Entretanto, 45,7% dos isolados continham a gene blaZ, indicando que a produção de beta-lactamases foi o principal mecanismo associado com a resistência dos Staphylococcus aos beta-lactâmicos. Os outros determinantes de resistência a agentes antimicrobianos ermA, ermb, ermC e msrA foram observados em 1,4%, 10,4%, 16,2% e 0,9% dos isolados respectivamente. Além disso, o gene icaD foi detectado em 32,9% dos isolados. Setenta e três isolados (54 de cabras e 19 de ovelhas) foram negativos para todos os genes de resistência testados e 69 isolados apresentaram dois ou mais genes de resistência. A associação entre blaZ, ermA, ermB, ermC e bomba de efluxo foi observada em 17 isolados dos quais 14 eram oriundos de cabras e três de ovelhas. Os dados obtidos no presente estudo indicam a resistência dos isolados aos beta-lactâmicos, o que pode estar associado ao uso sem controle veterinário destas drogas nos animais.

Actividad del (2E)-3-(2, 3-dimetoxifenil)-1-(4-metilfenil) prop-2-en-1-ona en presencia del poli(ácido maleico-co-2-vinil-pirrolidona) sobre un aislamiento clínico de Staphylococcus aureus / Activity of (2E)-3-(2, 3-dimetoxifenil)-1-(4-metilfenil) prop-2-en-1-ona in the presence of poli(maleic acid-co-2-vinyl-pyrrolidone)

Introducción: debido a la problemática actual de fármaco-resistencia hacia los antibióticos b-lactámicos, se ha hecho necesario, en busca de una solución, trabajar con nuevas moléculas con potencial farmacológico, así como utilizar novedosos sistemas poliméricos como matrices o excipientes farmacéuticos. Objetivo: evaluar la actividad antibiótica de la ampicilina, combinada con un compuesto sintético de tipo chalcona, denominado (2E)-3-(2,3-dimetoxifenil)-1-(4-metilfenil)prop-2-en- 1-ona, sobre un aislamiento clínico de Staphylococcus aureus resistente a penicilinas, en presencia de una matriz polimérica hidrosoluble denominada poli(ácido maleico-co-2-vinilpirrolidona). Materiales y métodos: el compuesto sintético y la matriz polimérica se obtuvieron por métodos descritos en la literatura. Se usó un aislamiento clínico de Staphylococcus aureus resistente a penicilinas y se hicieron ensayos de actividad antibiótica por la técnica de macrodilución en caldo, de la cual se obtuvieron las concentraciones inhibidoras mínimas de los compuestos evaluados. Resultados: la mezcla ampicilina-chalcona muestra un efecto antibiótico menor que el de su referente ampicilina-sulbactam. No obstante, cuando se utiliza la matriz polimérica en combinación con la ampicilina-chalcona se aprecia un incremento significativo de la actividad antibiótica, evidenciado en que la concentración inhibidora mínima es la mitad de la del referente comercial.

Introduction: Due to the current problem of resistance to b-lactam antibiotics, it has become necessary, in search of a solution, to work with new molecules with pharmacological potential, and to use novel polymeric systems as matrices or pharmaceutical excipients. Objective: To evaluate the antibiotic activity of ampicillin combined with a synthetic chalcone-type compound, the (2E)-3-(2,3-dimethoxyphenyl)-1-(4- methylphenyl) prop-2-en-1-one, on a clinical isolate of penicillin-resistant Staphylococcus aureus in the presence of a water soluble polymer matrix known as poly(maleic acid-co-2-vinyl-pyrrolidone). Materials and methods: The synthetic compound and the polymeric matrix were obtained by previously described methods. Tests for antibiotic activity against the strain of penicillin-resistant Staphylococcus aureus were done by the broth dilution technique which provided the minimal inhibitory concentrations of the compounds tested. Results: The chalcone-ampicillin mix shows lesser antibiotic effect than the ampicillin-sulbactam used as referent. However, when such mix is combined with the polymer matrix, antibiotic activity significantly increases as evidenced by decrease in the minimal inhibitory concentration with respect to the ampicillin-sulbactam referent.

Use of Boronic Acid Disks for the Detection of Extended-spectrum beta-lactamase and AmpC beta-lactamase in Escherichia coli, Klebsiella pneumoniae, Klebsiella oxytoca and Proteus mirabilis / 대한임상미생물학회지

BACKGROUND: Accurate detection of organisms producing extended-spectrum beta-lactamase (ESBL) and AmpC beta-lactamase is very important for treatment of patients. However, unlike the ESBL confirmatory test, there are no guidelines for detection of organisms producing AmpC beta-lactamase. We evaluated a detection method using boronic acid (BA) for ESBL and AmpC beta-lactamase. METHODS: Clinical isolates of Escherichia coli, Klebsiella pneumoniae, Klebsiella oxytoca, and Proteus mirabilis showing intermediate resistance or resistance to cefoxitin (FOX) or positive for ESBL were tested. A > or =5 mm increase in zone diameter of ceftazidime/clavulanic acid/BA (CAZ/CA/BA) and/or cefotaxime/clavulanic acid/BA (CTX/CA/BA) versus CAZ/BA and/or CTX /BA was considered positive for ESBL. Likewise, a > or =5 mm increase in zone diameter of FOX/BA and/or cefotetan/BA (CTT/BA) versus FOX and/or CTT alone was considered positive for AmpC beta-lactamase. RESULTS: Among 622 clinical isolates, ESBL positive rates by the CLSI ESBL confirmatory test or by the BA method were 18.1% or 18.4% for E. coli, 38.3% or 40.4% for K. pneumoniae, 8.7% or 8.7% for K. oxytoca, and 14.8% or 14.8% for P. mirabilis, respectively. AmpC beta-lactamase positive rates using the BA method were 3.7% for E. coli, 33.3% for K. pneumoniae, 0% for K. oxytoca, and 7.4% for P. mirabilis. The detection rates of coproducing ESBL and AmpC beta-lactamase were 2.4% in E. coli 27.1% in K. pneumoniae, and 3.7% in P. mirabilis. CONCLUSION: The ESBL confirmatory method using BA was found to enhance the detection of ESBLs, even when potentially masked by AmpC beta-lactamase.

Horizontol dissemination of TEM- and SHV-typr beta-lactamase genes-carrying resistance plasmids amongst clonical isolates of Enterobacteriaceae / Disseminação horizontal de plasmídios de resistência contendo genes de beta-lactamase dos tipos TEM e SHV entre isolados clínicos de Enterobacteriaceae

The extended-spectrum â-lactamase (ESBL)-producing bacteria have been isolated at increasing frequency worldwide. Expression of ESBL is often associated with multidrug resistance and dissemination by resistance plasmids. During a two-month period in 2000, 133 clinical isolates of enterobacterial strains were randomly collected from outpatients and inpatients at a university hospital in Turkey. The ESBL producing strains were determined by double-disk synergy (DDS) testing. Twenty ESBL producing strains (15 percent) including Escherichia coli (n = 9), Klebsiella pneumoniae (n = 7), Klebsiella oxytoca (n = 2) and Enterobacter aerogenes (n = 2) were detected and further analyzed for their resistance transfer features, plasmid profile and nature of the resistance genes. Plasmid transfer assays were performed using broth mating techniques. TEM- and SHV- genes were analyzed by polymerase chain reaction (PCR) and hybridization using specific probes. EcoRI restriction enzyme analyses of R plasmids were used in the detection of epidemic plasmids. Fourteen plasmid profiles (A, B1, B2, C1, and C2 to L) were obtained with EcoRI restriction enzyme analysis. Most of these plasmids were detected to carry both TEM- and SHV-derived genes by PCR, and confirmed by localizing each gene by hybridization assay. Epidemiological evidence indicated that there was an apparent horizontal dissemination of conjugative R plasmids among multidrug-resistant enterobacterial genera and species in this hospital

O isolamento de bactérias produtoras de beta-lactamases de espectro expandido (ESBL) está aumentando no mundo todo. Freqüentemente, a expressão de ESBL está associada com resistência a múltiplas drogas e disseminação por plasmídios de resistência. Durante um período de dois meses em 2000, 133 isolados clínicos de cepas de enterobactérias foram obtidos aleatoriamente de pacientes internos e externos de um hospital universitário na Turquia. As cepas produtoras de ESBL foram identificadas pelo teste de sinergia em disco-duplo (DDS). Foram detectadas vinte cepas produtoras de ESBL, entre as quais Escherichia coli (n=9), Klebsiella pneumoniae (n=7), Klebsiella oxytoca (n=2) e Enterobacter aerogenes (n=2), que foram posteriormente analisadas quanto a suas características de transferência de resistência, perfil plasmidial e natureza dos genes de resistência. Os testes de transferência de plasmídios foram realizados empregando técnicas de conjugação em caldo. Os genes TEM e SHV foram analisados pela reação da polimerase em cadeia (PCR) e hibridização com sondas especificas. A detecção de plasmídios epidêmicos foi feita por análise dos plasmídios R com a enzima de restrição EcoRI. Através desta análise, foram obtidos catorze perfis plasmidiais (A, B1, B2, C1 e C2 até L).Observou-se pela PCR que a maioria dos plasmidios carregavam genes derivados de TEM e SHV, confirmados através da detecção dos genes pelos testes de hibridização. As evidencias epidemiológicas indicaram que havia uma aparente transferência horizontal dos plasmídios R conjugativos entre as enterobactérias multiresistentes neste hospital.

Incidencia de cepas de bacterias gram negativas productoras de betalactamasas de espectro extendido en las Unidades de Cuidados Intensivos, hospital regional Doctor Teodoro Maldonado Carbo, 2004 – 2005 / Incidence of Gram negative bacteria strains extended spectrum beta-lactamases producing in the Intensive Care Units, Doctor Teodoro Maldonado Carbo regional hospital, 2004-2005

La producción de enzimas betalactamasas es el principal problema en las bacterias gram negativas y son la principal causa de infección nosocomial en unidades de cuidados intensivos. Tipo de estudio: transversal y prospectivo. Objetivos: con el fin de describir la importancia de estas bacterias en las unidades de cuidados intensivos del hospital “Dr. Teodoro Maldonado Carbo” de la ciudad de Guayaquil, se realizó un estudio para estimar la incidencia de este tipo de enzimas entre bacterias gram negativas resistentes. Método: la susceptibilidad de las muestras se analizó mediante concentración inhibitoria mínima en un microscan autoscan 4 de Dade Behring y con lectura visible según las recomendaciones del National Committee for Clinical Laboratory Standars. Para el análisis estadístico se empleó cálculo de estadígrafos y porcentajes. Resultados: 107 muestras fueron identificadas como bacterias gram negativas productoras de betalactamasas de espectro extendido constituyendo una prevalencia del 13.20 del total de muestras (n = 810), incidencia de 5.18 de todas las muestras solicitadas para cultivo y antibiograma (n=2.062). Las unidades de cuidados intensivos del hospital contribuyó con el 22.4 de las muestras que resultaron bacterias gram negativas productoras de betalactamasas de espectro extendido positivas y al 33.36 de las muestras enviadas desde hospitalización. La unidad de cuidados intensivos de neurología contribuyó con el 66.6 de las muestras de todas las unidades de cuidados intensivos y al 14 de todos los departamentos del hospital, la unidad de cuidados intensivos generales contribuyó con el 16. Conclusiones: la presencia de bacterias gram negativas productoras de betalactamasas de espectro extendido es un problema en la unidad de cuidados intensivos de neurología del hospital que se debe atender con efectividad y pertinencia.

Production of betalactamases enzymes is the main problema with Gram negative bacteria and the main cause of nosocomial infection in Intensive Care Units. Study type: Transversal and prospective. Objectives: in order to describe the importance of these bacteria in the “Dr. Teodoro Maldonado Carbo” Hospital (Guayaquil) intensive care units, a study has been made to appraise the incidence of this type of enzyme among resistant Gram negative bacteria. Method: susceptibility of the samples was analyzed through minimal inhibitory concentration in a Dade Behring microscan autoscan 4, and with visible reading according to the National Committee for Clinical Laboratory Standars advise. For statistical analysis calculation of statistic and percentages were used. Results: 107 samples were identified as Gram negative bacteria extended spectrum betalactamases producing, with a prevalence of 13.20 of all samples (n=810),an incidence of 5.18 of al samples required for culture and antibiogram (n=2062). The hospital intensive care units delivered the 22.4 of samples that turned out Gram negative bacteria positive extended spectrum betalactamases producing and 33.36 were samples sent from hospitalization. Neurology intensive care unit delivered 66.6 of the samples of all intensive care units, and 14 were sent from all hospital departments. General intensive care unit delivered 16. Conclusions: the presence of Gram negative bacteria extended spectrum betalactamases producing is a problem of the hospital Neurology intensive care unit that must be solved with effectiveness and appropriateness.

Isolation and analysis of circulating tuberculous antigens in Mycobacterium tuberculosis.

BACKGROUND: Serological techniques like enzyme linked immunosorbent assay (ELISA) and immunoblotting are useful for detection of mycobacterial antigens of diagnostic importance in tuberculosis. AIM: To isolate and identify circulating tuberculous antigens reactive with sputum positive and sputum negative pulmonary tuberculosis (PTB) sera. METHODS: Circulating tuberculous antigen was isolated by ammonium sulphate fractionation from the sera of sputum positive and sputum negative (clinically and radiologically diagnosed) PTB cases. The circulating antigen fractions and individual patients' serum samples were resolved by sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) and immunoblotting was performed using anti M.tb sonicate IgG as a probe to detect antigens. RESULTS: Anti M.tb sonicate IgG was found to be reactive with mycobacterial proteins 170 kDa, 140 kDa, 85 kDa, 55 kDa, 43 kDa, 20 kDa and 16 kDa in the antigen fraction isolated from sputum positive tuberculosis sera by immunoblotting. However only 85 kDa, 55kDa, 43 kDa and 20 kDa antigenic proteins were found to be recognized by anti sonicate IgG in the antigen isolated from sputum negative sera. These observations were further confirmed by analysis of individual S+ and S- PTB serum by immunoblotting. CONCLUSION: Seroreactive studies of circulating tuberculous antigens showed the presence of 170 kDa, 140 kDa, 85 kDa, 55 kDa, 43 kDa, 20 kDa and 16 kDa protein antigens in sputum positive sera, while 85 kDa, 55 kDa, 43 kDa and 20 kDa antigens were found to be present in sputum negative PTB which need further evaluation for their use in serological diagnosis of tuberculosis.

Study of beta lactamase activity of Staphylococcus aureus isolated from healthy nasal carriers and hospital isolates.

Staphylococcus aureus (n=84) isolated from the nostrils of a healthy population from Kathmandu and from the infectious cases (n=100) from Tribhuvan University Teaching Hospital, Kathmandu, Nepal were tested from May 1996 to March 1997 in Central Department of Microbiology, Tribhuvan University, Kathmandu, Nepal by microbiological and chemical methods to find out their beta lactamase activity. Among the healthy population, in domiciliary conditions 21.4% of the isolates were found beta lactamase producers. The occurrence of beta lactamase producing S. aureus was greater among female (27.0%) than among male (17.0%), however it was not significant (X2 = 1.2309, P > 0.05). The occurrence of the same was observed high among 40 and above age groups (66.7%) and 0-9 age group (60.0%), however no association with any particular age group was observed (X2 = 16.8674, P > 0.05). The b lactamase activity of S. aureus hospital inpatients isolates was 75.0% showing high occurrence of b lactamase activity in hospital isolates compared to S. aureus isolates from healthy carriers (X2 = 52.4113, P < 0.001). No association of beta lactamase positive hospital isolates with gender (X2 = 0.2158, P > 0.05) and age group (X2 = 1.5522, P > 0.05) was observed. This study shows that the prevalence of beta lactamase positive S. aureus was greater in hospital cases than in nasal carriers in domiciliary condition indicating the requisition of further study in this field.

Sífilis: reporte de un caso clínico / Syphilis: report of a clinical case

La sífilis es una enfermedad infecciosa cuya incidencia ha variado en el último siglo, aumentando desde la aparición de la infección por VIH. El objetivo de este artículo es describir un caso de sífilis secundaria en una paciente adolescente con múltiples lesiones bucales y genitales. El odontólogo debería ser capaz de realizar un correcto diagnóstico, reconociendo las manifestaciones clínicas y recurriendo a las pruebas de laboratorio que corresponden para esta enfermedad. Destacamos la importancia de detectar las lesiones bucales para encarar, junto al equipo multidisciplinario de salud, el tratamiento adecuado

Figures of penicillinase - producing neisseria gonorrhoeae at the Institute of Dermato-venereology, Hanoi, from 1992 to 2001

From 1992 to 2001, penicillin resistance of betalactamase-producing Neisseria gonorrhoeae was supervised by Institute of Dermato-Venereology. Results: the rate of penicillin-resistant gonococcal strains was highest in1995 (about 76%), and in 1996 (73.11%), especially in 3 years (1999-2001) this rate decreased significantly: 51.3%, 47.10%, and 35.54%, respectively

Methicillin Resistant Staphylococcal Infection: Report of 2 Cases

Determinación de la sensibilidad a diferentes antimicrobianos en Neisseria gonorrhoeae: comparación de dos métodos / Determination of the susceptibility to different antimicrobial agents in Neisseria gonorrhoeae: a comparison of two methods

Se aislaron 50 cepas de Neisseria gonorrhoeae de exudados uretrales y vaginales de pacientes que fueron atendidos en el Hospital Regional de Río Cuarto y de una Clínica Privada. La sensibilidad a 5 antimicrobianos fue realizada por 2 métodos: agar dilución y E-test (test-Epsilómetro PDM). La CIM (concentración inhibitoria mínima) alcanzada por el E-test fue ligeramente inferior a la lograda por el método clásico, observándose una relación significativa (P < 0,001) entre ambos métodos. Estos resultados muestran que el E-test es una alternativa interesante sobre el método de dilución en agar, siendo esta técnica apropiada para determinar la sensibilidad de N. gonorrhoeae a diferentes agentes antimicrobianos en el laboratorio clínico

ELISA using enzyme penicillinase for the detection of IgG antibodies to Trypanosoma evansi in sera of experimentally infected rabbits.

An Enzyme Linked Immunosorbent Assay (ELISA) using penicillinase as an enzyme marker has been developed for the detection of IgG antibodies in the sera of Trypanosoma evansi infected rabbits. Anti-T. evansi IgG antibodies were detected on 10th day after the infection and thereafter antibody titre rose progressively for 18 days. The developed assay is simple (end result assessed visually) and reproducible (4.4 and 14.0 percentage of intra and inter coefficient of variation respectively).

Producción y determinación de la actividad enzimática de la enzima penicilinasa / Determination and production of the enzymatic activity of the penicillinase enzyme

Este proyecto tiene como objetivo establecer una metodología para la producción y determinación de la actividad enzimática Penicilinasa, obtenida del cultivo de la cepa de bacillus licheniformis 749/c. Este microorganismo fue cultivado en caldo Tripticase-Soya por 5 días, seguidamente los sobrenadantes se reunieron y se sometieron a un proceso de esterilización. El título de Penicilinasa fue determinado acidimétricamente, lo que constituyó un índice de la cantidad de enzima acumulada durante el crecimiento. Para la determinación de la actividad enzimática se utilizó un método lodométrico. La esterilidad y eficacia del producto obtenido fue comprobada